CLDN7 and neoplasm: Previous studies associated the transcriptional repressive activity of Snail1 with the loss of expression of various epithelial genes in tumor cells, including the cell–cell contact genes CDH1 (Batlle et al., 2000; Cano et al., 2000) and CLAUDIN1 (Martinez‐Estrada et al., 2006), the ECM component MUC1 (Guaita et al., 2002), and the polarity regulator CRUMBS3 (Whiteman et al., 2008).